He is voiced by Derek Griffiths in the film and David Holt in the TV series.
Book and Movie
Vervain is the head of the Owslafa (Council police) in Efrafa. He is a large and bullying rabbit, more used to dealing with prisoners than with active combatants, and dislikes his peer Campion. As Efrafa's most-hated officer, Vervain depends upon General Woundwort's authority for his own. After the loss of Woundwort and the battle for Watership Down, Vervain is one of the retreating survivors killed by elil, but he had already lost heart and his sense of purpose. His name comes from an alternative name for verbena, a type of small flowering plant found in England.
In the TV series, Vervain is a cowardly and sneaky rabbit, more adept at spying on others and threatening the weaker ones than in actual combat. Despite his shortcomings, Woundwort values him (though he would not show this) for his loyalty to him. Although Campion saved his life on more than one occasion, Vervain hates him with a passion and would like nothing better than to make Woundwort realize Campion is a traitor. Kehaar is particularly not fond of Vervain and calls him 'ugly bunny'. After Efrafa's destruction, Vervain tries to live on his own but quickly loses hope, until he is saved by Woundwort. Although somewhat shocked by his master's increasing madness, Vervain continues to serve him, though more out of fear then respect, and he secretly longs to lead a different life, even if such thoughts are futile. Vervain's cowardice saves his life in the end, as by running away when the Black Rabbit of Inlé appears, he avoids the fate of Woundwort.